Evolutionary characteristics of infrared temperature field and micro analysis for Al/PTFE reactive materials in cook-off experiment

In order to reveal the microscopic characteristics of the sintered and unsintered aluminum/polytetrafluoroethylene (Al/PTFE) reactive materials at different stages in the cook-off experiment, the microscopic morphology and energy spectrum of the original samples, the samples before deflagration and deflagration products are characterized by scanning electron microscope (SEM) and energy dispersive spectrometer (EDS), respectively. Meanwhile, the temperature field distribution of the samples during the heat conduction process and the evolutionary process of the flame after deflagration are collected by the infrared thermal imager, respectively. The results show that the flow path of PTFE in the sintered sample is cross-linked in a network, and the PTFE in the unsintered sample is arranged in a dendritic manner. During the process of cook-off, there is an axial temperature gradient in the sample, and the PTFEs in the sintered and unsintered samples are distributed in bundles. The deflagration duration of the unsintered sample is shorter and the flame area is larger. The deflagration products of the sintered and unsintered samples contain smooth and massive crystalline substance aluminum fluoride, but the size of the crystalline substance in the unsintered sample is relatively large. In addition, the deflagration products of both sintered and unsintered samples have rough materials, and the outer surface of the sintered sample product is coated with fine fluorocarbon particles.